Hello
I have JK bms with 2A balance current controlling 16 Eve 280Ah cells that are configured into a 48V battery.
Issues I have is it appears that the BMS cycle count has jumped and is inaccurate (In use < 100 days, but cycle count is > 300).
One cell #14 jumps from 3.3V to 3.8V which then triggers charge shutdown for overvoltage, but it appears that the battery is not fully charged.
No.. I did not top balance this set of cells, as my understanding is that over many charge and discharge cycles the large 2A balance current available from the JK BMS will effectively execute a top Balance . (Andy in Australia says so for what it is worth.).
I am attaching some images from the JK BMS control screen, that shows that the "sense" wires all have low/suitable resistance, so I don't think the sense wires are the issue.
The batteries have the latest style top posts with two screws and the cell to cell bus bars have been tightened using a torque wrench.
Do I assume that the constant V jump of Cell 14 that disables the BMS due to cell overvoltage, appears to prevent the charger from fully charging the battery to be defective and replace it, or are there any other investigations of the unexpected Cell 14 behaviour, as well as the impossible BMS cycle count.
Note that as soon as charge is manually disabled cell 14 drops and is very well matched to the other cells (Note that all 16 cells are within .001 V with charge turned off, but as soon as charge is turned back on cell 14 V jumps up to 3.6-3.8 V and triggers the cell overvoltage protection.
See images of this Battery with low and higher state of charge, I don't believe I am getting anything close to the expected battery capacity from this battery, I am trying to establish battery capacity available and will update when I have that information.
I also have a hard time believing the JK BMS 98% charge level as correct with the reported voltages in the attached.
Thanks in advance
I have JK bms with 2A balance current controlling 16 Eve 280Ah cells that are configured into a 48V battery.
Issues I have is it appears that the BMS cycle count has jumped and is inaccurate (In use < 100 days, but cycle count is > 300).
One cell #14 jumps from 3.3V to 3.8V which then triggers charge shutdown for overvoltage, but it appears that the battery is not fully charged.
No.. I did not top balance this set of cells, as my understanding is that over many charge and discharge cycles the large 2A balance current available from the JK BMS will effectively execute a top Balance . (Andy in Australia says so for what it is worth.).
I am attaching some images from the JK BMS control screen, that shows that the "sense" wires all have low/suitable resistance, so I don't think the sense wires are the issue.
The batteries have the latest style top posts with two screws and the cell to cell bus bars have been tightened using a torque wrench.
Do I assume that the constant V jump of Cell 14 that disables the BMS due to cell overvoltage, appears to prevent the charger from fully charging the battery to be defective and replace it, or are there any other investigations of the unexpected Cell 14 behaviour, as well as the impossible BMS cycle count.
Note that as soon as charge is manually disabled cell 14 drops and is very well matched to the other cells (Note that all 16 cells are within .001 V with charge turned off, but as soon as charge is turned back on cell 14 V jumps up to 3.6-3.8 V and triggers the cell overvoltage protection.
See images of this Battery with low and higher state of charge, I don't believe I am getting anything close to the expected battery capacity from this battery, I am trying to establish battery capacity available and will update when I have that information.
I also have a hard time believing the JK BMS 98% charge level as correct with the reported voltages in the attached.
Thanks in advance